The present invention relates to a multi-part business form having form parts which may be interstacked (one form part overlapping another) and more specifically, to apparatus and methods for verifying registration of the form parts and to the forms therefor.
Presently, there is a need for a business form which is capable of being processed through a non-impact printer so that information can be printed on various, selected parts of the form, but which uses image transfer techniques for the addition of still further information to the form by an impact printer, or by manual means, such as a typewriter, etc. A business form of that type is described and illustrated in co-pending application Ser. No. 07/331,302, filed Mar. 31, 1989, entitled "Multiple Part Form for Non-Impact Printer and Related Process," of common assignee herewith, the disclosure of which is incorporated herein by reference.
The form of that invention can be processed through a non-impact printer, without activating the image transfer means, and thereafter rearranged so that cooperating pressure or impact responsive image transfer means are in position to transfer information applied to one sheet onto an underlying sheet.
More particularly, in that invention, a continuous web is divided into successive forms in a conventional manner by longitudinally spaced, transverse lines of perforations. A first longitudinally extending line of perforations is provided substantially centrally of the web (or to one or the other side of center, depending on desired form configuration) to define a stub portion when the web is subsequently slit longitudinally along a parallel indicator line, to thereby separate the web into first and second, transversely adjacent form parts. In accordance with that invention, the lower surface of the first form part is provided with a coating of carbonless microcapsules containing a liquid fill comprising a chemically reactive color-forming precursor, referred to as a CB (coated back) coating. At the same time, the upper surface of the adjacent or second form part is provided with a dry co-reactant resin coating referred to therein as a CF (coated front) coating. The CB and CF coatings comprise carbonless image transfer means of the type disclosed in U.S. Pat. No. 4,199,174.
Longitudinally extending feed holes are also provided along each marginal edge of the continuous web so that the web may be engaged by a conventional tractor drive mechanism for feeding the web through one or more processing stations. A third intermediate and longitudinally extending line of feed holes is provided adjacent the first longitudinal perforation line. In addition, a longitudinally extending glue line, for example, a heat seal type adhesive, is provided along, and inside, one marginal line of feed holes, but outside a second longitudinally extending perforation line, which defines a marginal stub portion. This type of form permits variable information to be applied to one or both form parts in a non-impact printer as the form passes therethrough in a two-wide (side-by-side), single-ply configuration. Subsequently, as briefly mentioned above, the web may be engaged by a conventional slitting mechanism which separates the form parts along the slit indicator line, a line adjacent the third, intermediate line of feed holes, but on the opposite side thereof, vis-a-vis the first longitudinal perforation line. Thus, two webs are formed with the form parts in each web remaining connected one to the other in the direction of web travel and with the form parts of each form lying transversely adjacent one another.
The separated parts are then interstacked by a conventional interstacking device, such that the first, and now upper, form part overlies the second, and now lower, form part so that the third intermediate (now marginal) line of feed holes of the lower form part are vertically aligned with the marginal feed holes of the upper form part. In that configuration, the CB coating on the back of the upper form part is in full surface engagement with the CF coating on the front of the lower form part so that, subsequently, information applied to the upper form part will be imaged onto the lower form part, through the interaction of the CB and CF coatings. After the form parts are interstacked and aligned, the heat-seal adhesive is activated to secure the respective form parts together.
The present invention relates to apparatus and methods relating to registration marks applied to the form for ensuring that the corresponding transversely adjacent form parts, when the webs and hence form parts are interstacked, lie in lengthwise registration with one another. The present invention also relates to the form on which the registration marks are applied. For purposes of this application, the form parts are in registration or registry with one another when the form parts are properly interstacked with appropriate perforation lines and tractor pin openings in alignment, and when the registration marks are aligned. Thus, the apparatus and methods, as well as the form, hereof are provided to ensure that when the form is slit lengthwise and the webs overlapped, both form parts of a form set lie in a predetermined lengthwise registration one with the other, i.e., are not misaligned in the lengthwise direction. In this application, lengthwise means the direction of the movement of the forms or form parts during manufacture including printing.
To accomplish the foregoing, a set of registration marks are provided on each of the form parts, preferably adjacent the left and right marginal edges of the form. The registration marks are applied to the form in transverse or lateral alignment with one another. The marks may be pre-printed on-line by a press or by an off-line printer. Each registration mark is comprised of discrete portions including a window mark portion and a count mark portion spaced lengthwise one from the other. Each of a predetermined sequentially arranged number of forms has a different set of registration marks, including a different number of counts in the count portion of the mark, such that a repeat of the count portion of the registration mark does not occur until several sets of marks and, hence, forms are moved past a sensing station, to be described. For example, the first set of registration marks in one form may have two counts in its count portion, with the succeeding marks in the next forms having three and four counts in their count portions, respectively, before the next set of two-count registration marks in the next form constitutes a repeat.
Preferably, by design the registration marks of each set thereof are complementary to one another. For example, one registration mark along one marginal edge of the form may have its window portion leading a trailing count portion while the other registration mark along the opposite marginal edge of the form may have its count portion leading a trailing window portion. In this manner, the forms can be run in opposite directions and the sensing apparatus hereof senses the marks when the forms are run in either direction. Additionally, there is a finite gap between the end of the leading window portion of the registration mark and the beginning of the window portion of the other registration mark of that set. Furthermore, the count portion of each set falls totally within the length of the window portion of the other registration mark of that set.
The apparatus for ensuring proper interstacking of the form parts includes a form conveyor having a plurality of tractor pins along its opposite sides for engaging the pin feed holes along one side of the form and the overlapped registering pin feed holes adjacent the other side of the interstacked form. An optical sensor is provided overlying the path of travel of each of the registration marks along the conveyor for detecting the registration marks. An encoder is provided to sense the rate, displacement and direction of travel of the conveyor and a microprocessor (CPU) is provided to compare the sensed registration marks and also to correlate them with the signals from the encoder in a manner set forth hereinafter.
The optical sensors are disposed to scan the path of travel of the registration marks when the interstacked form parts are located on the conveyor. When the first mark in a set appears under either sensor, its length is monitored. If the length is determined by the CPU to be longer than a predetermined length, it is taken as a window mark. Simultaneously, the opposite sensor scans the other registration mark of the set, particularly the count mark portion, and the count is stored by the CPU. Upon further movement of the form, the count mark portion of the first registration mark of that set is then sensed and the number of counts is stored in the CPU. Simultaneously, the window area of the second registration mark of that set is likewise sensed. After the second window mark passes the sensor, the two counts are compared. If the counts are the same, the form parts must lie in lengthwise registry. If they differ, an error signal is generated by the CPU and the conveyor is stopped. The CPU is programmed such that various error conditions may be noted and the conveyor stopped. For example, when no marks are sensed within the maximum length of the interstacked form, an error signal is generated which stops the conveyor. When the counts from the two form parts do not compare or are not equal, the CPU generates an error signal to stop the conveyor. Additionally, when the second window mark is not sensed within a predetermined distance of the end of the first window mark, an error signal is generated to likewise stop the conveyor.
In a preferred embodiment according to the present invention, there is provided a method for ensuring predetermined lengthwise registration of at least partially superposed form parts forming a form, comprising the steps of providing first and second form parts, each having a registration mark identifying the first and second form parts as parts of a first form, overlapping portions of the first and second form parts and sensing the registration marks of the overlapped first and second form parts to determine a characteristic thereof and providing output signals responsive thereto. Predetermined criteria are established for comparing the sensed characteristics of the registration marks. The output signals are compared and an error signal is provided in response to a comparison of the sensed characteristics of the registration marks in the event the sensed characteristics do not compare according to the predetermined criteria, thereby indicating a lack of registration of the first and second form parts.
In a further preferred embodiment according to the present invention, there is provided a form for use in interstacking form parts thereof comprising first and second form parts attached to one another and severable one from the other to provide discrete form parts for interstacking one with the other. Each form part carries a registration mark for ensuring predetermined lengthwise registration of the interposed form parts, with each registration mark including a pair of discrete mark portions spaced one from the other in the lengthwise direction, the registration mark on one of the form parts being the complement of the registration mark on the other of the form parts.
In a further preferred embodiment according to the present invention, there is provided apparatus for interstacking form parts of a continuous form web and ensuring predetermined lengthwise registration of at least the partially superposed form parts forming a form comprising means for conveying a form web in a predetermined direction of travel, the form web having a plurality of forms spaced one from the other in the direction of web travel, with each form having a pair of transversely spaced first and second form parts. Means are provided for separating and interstacking the form parts and for sensing a registration mark on each of the first and second form parts identifying the first and second form parts as parts of a specified form to determine a characteristic thereof and providing an output signal in response thereto. Means are also provided for establishing a predetermined criteria for comparing the sensed characteristics of the registration marks. Finally, means for comparing the output signals and providing an error signal in response to a comparison of the sensed characteristics of the registration marks in the event the sensed characteristics do not compare according to the predetermined criteria are also provided, thereby indicating a lack of registration of the first and second form parts.
Accordingly, it is a primary object of the present invention to provide novel and improved apparatus and methods for verifying registration of interstacked form parts and the forms therefor.
These and further objects and advantages of the present invention will become more apparent upon reference to the following specification, appended claims and drawings.